Another favorite of mine is the Google Sky Map I have on my Droid X. Uses the GPS locator function to help identify the stars. Just hold it in the direction you are looking and it shows a map listingof all thestars, planets, satellites in the same direction. Lots of fun when sitting outside on a clear night being able to locate and identify different constellations.
2005 CF29RE 04 Ford F250 crew 6.0 P/stroke FX-4.
(pic coming soon!)